News & Research

    University of Illinois at Chicago, Chicago, Illinois

Role of common food additive carrageenan in etiology of Type 2 diabetes

General Research Subject: Type 2 Diabetes

Focus: Insulin Action\Insulin Resistance, Insulin Action\Signal Transduction, Nutrition-Clinical

Type of Grant: Basic Science

Project Start Date: January 1, 2012

Project End Date: December 31, 2014

Diabetes Type: Type 2 diabetes

Research Description

Carrageenan is a common food additive in the diet, and its consumption has increased in recent decades. It is composed of sugar (galactose) molecules that are either sulfated or unsulfated. Although a natural product obtained from red seaweed, it is well-known to cause inflammation. Carrageenan has been used in thousands of experiments to produce inflammation, since its unusual chemical structure induces an innate immune response. In some of the experiments performed in my laboratory, mice were given carrageenan in their water at a concentration less than what is expected to be consumed in the typical diet. These mice had abnormal glucose tolerance tests compared to controls not given carrageenan. High glucose levels were associated with high insulin levels, indicating resistance to the effects of insulin. Other experiments showed impairment of the insulin signaling pathway in human colonic cells following carrageenan, as well as in the mouse liver tissue. Since average consumption of carrageenan in the adult diet is estimated to be 250 mg/day, it is important to determine whether or not carrageenan consumption is a significant factor in the increasing prevalence of diabetes. The experiments proposed in this project will provide evidence of whether or not carrageenan exposure causes insulin resistance and glucose intolerance and provide insight into the molecular mechanisms that are affected by carrageenan. Since carrageenan intake can be reduced by either dietary choices or regulation, determining the impact of carrageenan on glucose tolerance is highly relevant to the purposes of the ADA.

Research Profile

What area of diabetes research does your project cover? What role will this particular project play in preventing, treating or/curing diabetes?

This project covers the relationship between intake of the common food additive carrageenan and the development of glucose intolerance. By attention to the impact of a specific, common dietary ingredient, new interventions to prevent and treat diabetes may be developed.

If a person with diabetes were to ask you how your project will help them in the future, how would you respond?

This project may provide new insight into how diet affects development and progression of diabetes. By elimination of carrageenan-containing foods from the diet, individuals may be at reduced risk for diabetes and management of diabetes may improve.

Why is it important for you, personally, to become involved in diabetes research? What role will this award play in your research efforts?

As a physician, I have treated many patients with diabetes and seen the severe morbidity and suffering that can arise from diabetes. The initial findings from my laboratory that demonstrate profound effects of carrageenan exposure on glucose tolerance, insulin sensitivity, and insulin signaling indicate that carrageenan in food may have an important role in diabetes. I personally will find it very gratifying to know if exposure to carrageenan and the associated inflammation contribute to the development and the severity of diabetes and if elimination of exposure to carrageenan can reduce the occurrence and/or severity of diabetes. This award will enable this research to move ahead.

In what direction do you see the future of diabetes research going?

Diabetes is a multi-system disorder, so specific manifestations of the disorder in different organs need to be explained. The elucidation of the role of inflammation in insulin signaling may help to explain to some extent the overall metabolic derangement, but the integration of the effects of inflammation on carbohydrate, lipid, and protein metabolism in different organs will require new insights into mechanisms of regulation. I think that the work that we are doing with carrageenan may have significant implications for a wide range of cellular processes, since carrageenan inhibits sulfatase enzymes, which perform several specified, vital cell functions that are relatively understudied.